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Indications of structural changes in the marine ecosystem, catch ratios of predatory and plankton feeding fish Indications of structural changes in the marine ecosystem, catch ratios of predatory and plankton feeding fish
Three-quarters of fish stocks are currently exploited to the maximum extent, if not excessively. The Northeast Atlantic Ocean continues to exhibit declining catches, as well as a shift towards fish at lower levels in the food chain. This graphic illustrates the decline in the catch ratios of predatory and plankton-feeding fish in the Northeast Atlantic Ocean from 1950 to 1995.
17 May 2005 - by Philippe Rekacewicz, UNEP/GRID-Arendal
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Indications of structural changes in the marine ecosystem, catch ratios of predatory and plankton feeding fish Indications of structural changes in the marine ecosystem, catch ratios of predatory and plankton feeding fish
Three-quarters of fish stocks are currently exploited to the maximum extent, if not excessively. The Northeast Atlantic Ocean continues to exhibit declining catches, as well as a shift towards fish at lower levels in the food chain. This graphic illustrates the decline in the catch ratios of predatory and plankton-feeding fish in the Northeast Atlantic Ocean from 1950 to 1995.
17 May 2005 - by Philippe Rekacewicz, UNEP/GRID-Arendal
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Renewable freshwater supplies, per river basin Renewable freshwater supplies, per river basin
Freshwater represents a crucial sort for human development, for nature and for ecosystem services. This graphic compares freshwater supplies in cubic metres per capita, per river basin in 1995 with a projection of freshwater supplies for the same areas in 2025. The graphic shows which areas were experiencing water stress, which were experiencing water scarcity and which had sufficient quantities of freshwater in 1995, and shows projections for th...
17 May 2005 - by Philippe Rekacewicz, UNEP/GRID-Arendal
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Renewable freshwater supplies, per river basin Renewable freshwater supplies, per river basin
Freshwater represents a crucial sort for human development, for nature and for ecosystem services. This graphic compares freshwater supplies in cubic metres per capita, per river basin in 1995 with a projection of freshwater supplies for the same areas in 2025. The graphic shows which areas were experiencing water stress, which were experiencing water scarcity and which had sufficient quantities of freshwater in 1995, and shows projections for th...
17 May 2005 - by Philippe Rekacewicz, UNEP/GRID-Arendal
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Nigeria and the freshwater challenge Nigeria and the freshwater challenge
Out of the total precipitation reaching Nigeria, it can be separated into green and blue water. Green water (79% of the precipitation) represents the fraction of rainfall that generates soil moisture and which supports terrestrial ecosystems. It is not returned to groundwater and rivers, but will eventually evaporate or transpire through plants. Blue water, on the other hand, represents the fraction (21%) of the precipitation that runs into river...
02 Nov 2006 - by Hugo Ahlenius, UNEP/GRID-Arendal
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Nigeria and the freshwater challenge Nigeria and the freshwater challenge
Out of the total precipitation reaching Nigeria, it can be separated into green and blue water. Green water (79% of the precipitation) represents the fraction of rainfall that generates soil moisture and which supports terrestrial ecosystems. It is not returned to groundwater and rivers, but will eventually evaporate or transpire through plants. Blue water, on the other hand, represents the fraction (21%) of the precipitation that runs into river...
02 Nov 2006 - by Hugo Ahlenius, UNEP/GRID-Arendal
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Origin and destination of selected invasive/alien species Origin and destination of selected invasive/alien species
Invasive and alien species that are brought into a new environment, either on purpose or by accident, can quickly exploit ecological niches that are not fully covered by indigenous (local) species. They will then quickly spread and outcompete the local wildlife.
29 Nov 2007 - by Philippe Rekacewicz, UNEP/GRID-Arendal
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Origin and destination of selected invasive/alien species Origin and destination of selected invasive/alien species
Invasive and alien species that are brought into a new environment, either on purpose or by accident, can quickly exploit ecological niches that are not fully covered by indigenous (local) species. They will then quickly spread and outcompete the local wildlife.
29 Nov 2007 - by Philippe Rekacewicz, UNEP/GRID-Arendal
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Origin and destination of selected invasive/alien species Origin and destination of selected invasive/alien species
Invasive and alien species that are brought into a new environment, either on purpose or by accident, can quickly exploit ecological niches that are not fully covered by indigenous (local) species. They will then quickly spread and outcompete the local wildlife.
29 Nov 2007 - by Philippe Rekacewicz, UNEP/GRID-Arendal
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How the comb-jelly (Mnemiopsis leidyi) is spreading through European seas (invasive species) How the comb-jelly (Mnemiopsis leidyi) is spreading through European seas (invasive species)
The most threatening event for the Caspian ecosystem was the arrival of the North American comb jelly (Mnemiopsis leidyi). It was brought accidentally to the Caspian in the ballast water of oil tankers. Invasive and alien species can exploit ecological niches that are not currently occupied, and spread rapidly, out-competing indigenous species.
29 Nov 2007 - by Philippe Rekacewicz, UNEP/GRID-Arendal
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How the comb-jelly (Mnemiopsis leidyi) is spreading through European seas (invasive species) How the comb-jelly (Mnemiopsis leidyi) is spreading through European seas (invasive species)
The most threatening event for the Caspian ecosystem was the arrival of the North American comb jelly (Mnemiopsis leidyi). It was brought accidentally to the Caspian in the ballast water of oil tankers. Invasive and alien species can exploit ecological niches that are not currently occupied, and spread rapidly, out-competing indigenous species.
29 Nov 2007 - by Philippe Rekacewicz, UNEP/GRID-Arendal
5
How the comb-jelly (Mnemiopsis leidyi) is spreading through European seas (invasive species) How the comb-jelly (Mnemiopsis leidyi) is spreading through European seas (invasive species)
The most threatening event for the Caspian ecosystem was the arrival of the North American comb jelly (Mnemiopsis leidyi). It was brought accidentally to the Caspian in the ballast water of oil tankers. Invasive and alien species can exploit ecological niches that are not currently occupied, and spread rapidly, out-competing indigenous species.
29 Nov 2007 - by Philippe Rekacewicz, UNEP/GRID-Arendal
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Biodiversity loss: state and scenarios 2006 and 2050 Biodiversity loss: state and scenarios 2006 and 2050
These projections of biodiversity loss from 2000 to 2050 were produced by the GLOBIO consortium for UNEP's Global Environment Outlook 4. Across the GEO scenarios and regions, global biodiversity continues to be threatened, with strong implications for ecosystem services and human well-being. All regions continue to experience declines in terrestrial biodiversity in each of the scenarios. The greatest losses are seen in Markets First, followed by ...
26 Jan 2006 - by Hugo Ahlenius, UNEP/GRID-Arendal
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Uganda: quantifying the importance of environment and natural resources Uganda: quantifying the importance of environment and natural resources
Estimations calculate that the environment and natural resources sector should contribute USD 791 million to the Uganda GDP, excluding benefits like ecosystem services. In the formal figures, only USD 405 million is recorded, where subsistence use and informal markets are not captured. Over 90% of the employment in the sector is secondary processing and subsistence use. Sustainable natural resource use implies that this sector will continue to pr...
02 Nov 2006 - by Hugo Ahlenius, UNEP/GRID-Arendal
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Arctic delta pond ecosystems, seasonal flooding and adaptation Arctic delta pond ecosystems, seasonal flooding and adaptation
The physical development and ecosystem health of river deltas in cold regions are strongly controlled by ice processes and thus are highly susceptible to the effects of climate change. As an example, the photograph shows a typical lake/pond and river network in the Peace-Athabasca Delta (Canada), one of the largest freshwater deltas in the world. The water budget and sediment-nutrient supply for the multitude of lakes and ponds that dot the ripar...
01 Nov 2007 - by Hugo Ahlenius, UNEP/GRID-Arendal
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Forest systems Forest systems
Forest systems are lands dominated by trees; they are often used for timber, fuelwood, and non-wood forest products. The map shows areas with a canopy cover of at least 40% by woody plants taller than 5 meters.
30 Nov 2007 - by Philippe Rekacewicz, Emmanuelle Bournay, UNEP/GRID-Arendal
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Economic benefits under alternate management practices Economic benefits under alternate management practices
In each case, the net benefits from the more sustainably managed ecosystem are greater than those from the converted ecosystem, even though the private (market) benefits would be greater from the converted ecosystem.
30 Nov 2007 - by Philippe Rekacewicz, Emmanuelle Bournay, UNEP/GRID-Arendal
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Growth in number of marine species introductions Growth in number of marine species introductions
Number of new records of established non-native invertebrate and algal species reported in marine waters of North America, shown by date of first record, and number of new records of non-native marine plant species reported on the European coast, by date of first record.
30 Nov 2007 - by Philippe Rekacewicz, Emmanuelle Bournay, UNEP/GRID-Arendal
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Inland water and mountain systems Inland water and mountain systems
Inland water systems are permanent water bodies inland from the coastal zone and areas whose properties and use are dominated by the permanent, seasonal, or intermittent occurrence of flooded conditions. Inland waters include rivers, lakes, floodplains, reservoirs, wetlands, and inland saline systems.
30 Nov 2007 - by Philippe Rekacewicz, Emmanuelle Bournay, UNEP/GRID-Arendal
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Trend in mean depth of catch since 1950 Trend in mean depth of catch since 1950
Fisheries catches increasingly originate from deep areas. Over the years due to depletion in fish stocks the fishing industry has resorted to fishing at greater depths and increasing the damage to fish stocks and the ocean floor.
30 Nov 2007 - by Philippe Rekacewicz, Emmanuelle Bournay, UNEP/GRID-Arendal
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